Cellulose-ether composition



Patented Sept. 4, .1923.

UNITED STATES PATENT OFFICE.

STEWART J. CARROLL, OF ROCHESTER, NEW YORK, ASSIGNOR TO EASTMAN KODAK COMPANY, OF ROCHESTER, NEW YORK, A. CORPORATION OF NEW YORK.

CELLULOSE-ETHER COMPOSITION.

Ho Drawing.

To all whom it may concern.

Be it known that I, STEWART J. CARR LL, a citizen of the United States of Amerlca, residing at Rochester, in the county of Monroe and State of New York, have invented certain. new and useful Improvements in Cellulose-Ether Compositions, of which the following is a full, clear, and exact specification.

This invention relates to solvents for cellulose ethers and to compositions produced by the aid of such solvents. One object of the invention is to provide a solvent which will readily dissolve cellulose ethers and make as strong solutions as may be required 1n the varnish and plastic arts, including solutions sufficiently viscous for film manufacture. Another object of the invention is to provide cellulose ether compositions which may be made into strong flexible transparent film. Other objects will hereinafter appear.

I have discovered that these objects may be attained by mixing cyclohexanol with certain alkyl compounds and by dissolving cellulose ether in the mixture. This mixture has a much eater solvent action than the sum of the so vent actions of its constituents when used alone. In fact cyclohexanol alone has practically no solvent power for the ethers. The alkyl compounds which I may employ are the monohydroxy aliphatic alcohols containing less than six carbon atoms, acetates of such alcohols, and mixtures of these, and I designate these by the expression, a compound based upon a monohydroxy aliphatic alcohol containing less than 6 carbon atoms. In the preferred embodiments of my invention I prefer to use the more volatile of these compounds such as methyl alcohol, ethyl alcohol, methyl ace-' tate, or ethyl acetate.

By way of example I may mix from 10 to parts by weight of cyclohexanol with 90 to 50 parts of ethyl acetate. A 50 to 50 mixture of cyclohexanol and ethyl acetate, for instance, will dissolve from one-fourth to one-sixth (say one-fifth) of its own weight of water-insoluble ethyl cellulose to form a thick, viscous, flowable solution suitable for film manufacture in the usual way.

Other substances which impart useful properties to the, film may be added to the Application filed March 3, 1922. Serial No. 540,808

fiowable composition such, for example, as triphenyl or tricresyl phosphate, camphor, monochlornaphthalene, etc. The ingredients are of the commercial type, sufliciently purified to give film having the desired freedom from color. On account of its relatively higher boiling point cyclohexanol evaporates more slowly and sufficient amounts of it remain in the film to increase the useful properties of the latter.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A composition of matter comprising cellulose ether and cyclohexanol.

2. A composition of matter, comprising cellulose ether dissolved in a mixture of cyclohexanol and aliquid compound which coacts with said cyclohexanol to give said mixture greater solvent action on the cellulose ether'than the sum of the solvent actions of its said constituents used alone, said liquid .compound'being based upon a monohydroxy aliphatic alcohol containing less than 6 car bon atoms.

3. A composition of matter comprising cellulose ether, cyclohexanol and ethyl acetate.

4. A viscous, fiowable, film-forming composition, comprising 1 part by weight of cellulose ether dissolved in from 4 to 6 parts of a mixture containing cyclohexanol and a liquid compound which coacts with said cyclohexanol to give said mixture greater solvent action on the cellulose other than the sum of the solvent actions of its said con- 

